Diesel vehicles are sometimes equipped with an exhaust brake. Generally speaking, the exhaust brake is a mechanism that slows a diesel engine by closing off the exhaust path from the engines. This causes the exhaust gases to be compressed in the exhaust manifold and the cylinder. An exhaust brake is typically in the form of a valve (butterfly valve) in the exhaust system that is capable of being closed to restrict the exhaust flow. When the exhaust brake is operational (i.e., when the exhaust brake is on or is in an operational state), the valve forming the exhaust brake closes when the driver releases the accelerator pedal (i.e., wishes to decelerate the vehicle). With the valve in the closed condition, the exhaust flow from the cylinders is restricted and so pressure builds up in the exhaust system upstream from the exhaust brake. This creates a pressure on the top of the piston to resist upward movement of the piston, thus supplying a braking torque that slows the engine and the vehicle without the need for operating the vehicle's service brake. When the exhaust brake is operational (i.e., when the exhaust brake is on or is in an operational state), the valve forming the exhaust brake opens when the accelerator pedal is depressed so that the exhaust brake does not slow the vehicle engine/vehicle.
As illustrated in FIG. 1, the exhaust brake is operated by a toggle-type switch (exhaust brake switch) connected to an engine control unit (ECU) 12. The engine 14 in turn is connected to the ECU 12. This known toggle-type exhaust brake switch is operable by the user (driver) to turn the exhaust brake on so that the exhaust brake is in an operational state and to turn the exhaust brake off so that the exhaust brake is in a non-operational state. When the driver turns the toggle-type exhaust brake switch on, the toggle-type switch remains on until the driver once again operates the toggle-type exhaust brake switch. If the driver operates the exhaust brake switch during operation of the vehicle to turn the exhaust brake to the operational state, and then turns the vehicle off (i.e., the ignition is turned off) without operating the toggle-type exhaust brake switch to turn the exhaust brake to the non-operational state, the exhaust brake will still be in the operational state when the vehicle is next turned on (started). This is illustrated schematically in FIG. 2.